| Classification | Pseudocylindrical |
| Available forms | Forward and inverse, spherical projection |
| Defined area | Global |
| Alias | fouc_s |
| Domain | 2D |
| Input type | Geodetic coordinates |
| Output type | Projected coordinates |
proj-string: +proj=fouc_s
The y-axis is based upon a weighted mean of the cylindrical equal-area and the sinusoidal projections. Parameter n=n is the weighting factor where 0 <= n <= 1.
x &= \lambda \cos \phi / (n + (1 - n) \ cos \phi)
y &= n \phi + (1 - n) \sin \phi
For the inverse, the Newton-Raphson method can be used to determine \phi from the equation for y above. As n \rightarrow 0 and \phi \rightarrow \pi/2, convergence is slow but for n = 0, \phi = \sin^1y
Note
All parameters are optional for the Foucaut Sinusoidal projection.
.. option:: +n=<value>
Weighting factor. Value should be in the interval 0-1.